Transcapacitive sensor devices with ohmic seams

ABSTRACT

A transcapacitive sensing device has and ohmic seam which sections a plurality of transmitter electrodes and also sections a plurality of receiver electrodes. A processing system is communicatively coupled with the transmitter electrodes and the receiver electrodes and configured to: transmit a first transmitter signal with a first transmitter electrode disposed on a first side of the ohmic seam; transmit a second transmitter signal with a second transmitter electrode disposed on a second side of the ohmic seam; receive a first response corresponding to said first transmitter signal with a first receiver electrode disposed on the first side of the ohmic seam; and receive a second response corresponding to said second transmitter signal with a second receiver electrode disposed on the second side of the ohmic seam.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to and benefit of co-pending U.S.provisional patent application 61/288,124, titled “METHOD AND APPARATUSFOR CAPACITIVE SENSING ON LARGE TOUCH SCREENS,” filed Dec. 18, 2009 andassigned to the assignee of the present non-provisional application,which is herein incorporated by reference in its entirety.

BACKGROUND

Input devices including proximity sensor devices (also commonly calledtouchpads or touch sensor devices) are widely used in a variety ofelectronic systems. A proximity sensor device typically includes asensing region, often demarked by a surface, in which the proximitysensor device determines the presence, location and/or motion of one ormore input objects. Proximity sensor devices may be used to provideinterfaces for the electronic system. For example, proximity sensordevices are often used as input devices for larger computing systems(such as opaque touchpads integrated in, or peripheral to, notebook ordesktop computers). Proximity sensor devices are also often used insmaller computing systems (such as touch screens integrated in cellularphones).

SUMMARY

A transcapacitive sensing device has an ohmic seam, a plurality oftransmitter electrodes, a plurality of receiver electrodes, and aprocessing system. The plurality of transmitter electrodes is sectionedby the ohmic seam. The plurality of receiver electrodes is alsosectioned by the ohmic seam. The processing system is communicativelycoupled with the plurality of transmitter electrodes and the pluralityof receiver electrodes. The processing system is configured to: transmita first transmitter signal with a first transmitter electrode of theplurality of transmitter electrodes, wherein the first transmitterelectrode is disposed on a first side of the ohmic seam; transmit asecond transmitter signal with a second transmitter electrode of theplurality of transmitter electrodes, wherein the second transmitterelectrode is disposed on a second side of the ohmic seam; receive afirst response corresponding to the first transmitter signal with afirst receiver electrode of the plurality of receiver electrodes,wherein the first receiver electrode is disposed on the first side ofthe ohmic seam; and receive a second response corresponding to thesecond transmitter signal with a second receiver electrode of theplurality of receiver electrodes, wherein the second receiver electrodeis disposed on the second side of the ohmic seam.

BRIEF DESCRIPTION OF DRAWINGS

The drawings referred to in this Brief Description of Drawings shouldnot be understood as being drawn to scale unless specifically noted. Theaccompanying drawings, which are incorporated in and form a part of theDescription of Embodiments, illustrate various embodiments of thepresent invention and, together with the Description of Embodiments,serve to explain principles discussed below, where like designationsdenote like elements, and:

FIG. 1 is a block diagram of an example input device, in accordance withembodiments of the invention;

FIG. 2 shows a portion of an example capacitive sensor pattern which maybe used to implement a sensing region, according to an embodiment;

FIG. 3 shows an example sensor pattern that has been divided into twosections by an ohmic seam, according to an embodiment;

FIG. 4 shows an example sensor pattern that has been divided into threesections by two non-intersecting ohmic seams, according to anembodiment;

FIG. 5 shows an example sensor pattern that has been divided into foursections by two intersecting ohmic seams, according to an embodiment;

FIG. 6 shows the layout of an example four-section sensor pattern withsensor electrodes that are simple rectangles in shape, according to anembodiment;

FIG. 7 shows a layout of an example four-section sensor electrode sensorpattern with sensor electrodes that are not merely simple rectangles inshape, according to an embodiment;

FIGS. 8 and 9 illustrate two examples of a sensor patterns with spitpixels, according to various embodiments;

FIGS. 10-12 show example multi-sectioned sensor patterns along withexample sensing schemes with coding patterns, according to variousembodiments;

FIG. 13 and FIG. 14 illustrate how multiple integrated circuits may beutilized by some input devices, according to some embodiments;

FIG. 15 illustrates an example processing system which may be utilizedwith an input device, according to various embodiments; and

FIG. 16A and FIG. 16B illustrate a flow diagram of an example method ofcapacitive sensing with a capacitive sensing device comprising aplurality of transmitter electrodes sectioned by an ohmic seam and aplurality of receiver electrodes sectioned by the ohmic seam, accordingto various embodiments.

DESCRIPTION OF EMBODIMENTS

The following Description of Embodiments is merely is provided by way ofexample and not of limitation. Furthermore, there is no intention to bebound by any expressed or implied theory presented in the precedingtechnical field, background, brief summary or the following detaileddescription.

Various embodiments of the present invention provide input devices andmethods that facilitate improved usability.

Turning now to the figures, FIG. 1 is a block diagram of an exemplaryinput device 100, in accordance with embodiments of the invention. Theinput device 100 may be configured to provide input to an electronicsystem (not shown). As used in this document, the term “electronicsystem” (or “electronic device”) broadly refers to any system capable ofelectronically processing information. Some non-limiting examples ofelectronic systems include personal computers of all sizes and shapes,such as desktop computers, laptop computers, netbook computers, tablets,web browsers, e-book readers, and personal digital assistants (PDAs).Additional example electronic systems include composite input devices,such as physical keyboards that include input device 100 and separatejoysticks or key switches. Further example electronic systems includeperipherals such as data input devices (including remote controls andmice), and data output devices (including display screens and printers).Other examples include remote terminals, kiosks, and video game machines(e.g., video game consoles, portable gaming devices, and the like).Other examples include communication devices (including cellular phones,such as smart phones), and media devices (including recorders, editors,and players such as televisions, set-top boxes, music players, digitalphoto frames, and digital cameras). Additionally, the electronic systemcould be a host or a slave to the input device.

The input device 100 can be implemented as a physical part of theelectronic system, or can be physically separate from the electronicsystem. As appropriate, the input device 100 may communicate with partsof the electronic system using any one or more of the following: buses,networks, and other wired or wireless interconnections. Examplesinclude, but are not limited to: Inter-Integrated Circuit (I²C), SerialPeripheral Interface (SPI), Personal System 2 (PS/2), Universal SerialBus (USB), Bluetooth, Radio Frequency (RF), and Infrared DataAssociation (IrDA).

In FIG. 1, the input device 100 is shown as a proximity sensor device(also often referred to as a “touchpad” or a “touch sensor device”)configured to sense input provided by one or more input objects 140 in asensing region 120. Example input objects include fingers and styli, asshown in FIG. 1.

Sensing region 120 encompasses any space above, around, in and/or nearthe input device 100 in which the input device 100 is able to detectuser input (e.g., user input provided by one or more input objects 140).The sizes, shapes, and locations of particular sensing regions may varywidely from embodiment to embodiment. In some embodiments, the sensingregion 120 extends from a surface of the input device 100 in one or moredirections into space until signal-to-noise ratios prevent sufficientlyaccurate object detection. The distance to which this sensing region 120extends in a particular direction, in various embodiments, may be on theorder of less than a millimeter, millimeters, centimeters, or more, andmay vary significantly with the type of sensing technology used and theaccuracy desired. Thus, some embodiments sense input that comprises nocontact with any surfaces of the input device 100, contact with an inputsurface (e.g., a touch surface) of the input device 100, contact with aninput surface of the input device 100 coupled with some amount ofapplied force or pressure, and/or a combination thereof. In variousembodiments, input surfaces may be provided by surfaces of casingswithin which the sensor electrodes reside, by face sheets applied overthe sensor electrodes or any casings, etc. In some embodiments, thesensing region 120 has a rectangular shape when projected onto an inputsurface of the input device 100.

The input device 100 may utilize any combination of sensor componentsand sensing technologies to detect user input in the sensing region 120.The input device 100 comprises one or more sensing elements fordetecting user input. As several non-limiting examples, the input device100 may use acoustic, ultrasonic, capacitive, elastive, resistive,inductive, and/or optical techniques.

Some implementations are configured to provide images that span one,two, three, or higher dimensional spaces. Some implementations areconfigured to provide projections of input along particular axes orplanes.

In some capacitive implementations of the input device 100, voltage orcurrent is applied to create an electric field. Nearby input objectscause changes in the electric field, and produce detectable changes incapacitive coupling that may be detected as changes in voltage, current,or the like.

Some capacitive implementations utilize arrays or other regular orirregular patterns of capacitive sensing elements to create electricfields. In some capacitive implementations, separate sensing elementsmay be ohmically shorted together to form larger sensor electrodes. Somecapacitive implementations utilize resistive sheets, which may beuniformly resistive.

Some capacitive implementations utilize “mutual capacitance” (or“transcapacitance”) sensing methods based on changes in the capacitivecoupling between sensor electrodes. In various embodiments, an inputobject near the sensor electrodes alters the electric field between thesensor electrodes, thus changing the measured capacitive coupling. Inone implementation, a transcapacitive sensing method operates bydetecting the capacitive coupling between one or more transmitter sensorelectrodes (also “transmitter electrodes” or “transmitters”) and one ormore receiver sensor electrodes (also “receiver electrodes” or“receivers”). Transmitter sensor electrodes may be modulated relative toa reference voltage (e.g., system ground) to transmit transmittersignals, and receiving sensor electrodes may be held substantiallyconstant relative to the reference voltage to facilitate receipt ofresulting signals. The resulting signals may comprise one or moreresponses, each response corresponding to one of the transmittersignals. Sensor electrodes may be dedicated transmitter electrodes orreceiver electrodes, or may be configured to both transmit and receive.

In FIG. 1, a processing system (or “processor”) 110 is shown as part ofthe input device 100. The processing system 110 is configured to operatethe hardware of the input device 100 to detect input in the sensingregion 120. The processing system 110 comprises parts of or all of oneor more integrated circuits (ICs) and/or other circuitry components; insome embodiments, the processing system 110 also compriseselectronically-readable instructions, such as firmware code, softwarecode, and/or the like. In some embodiments, components composing theprocessing system 110 are located together, such as near sensingelement(s) of the input device 100. In other embodiments, components ofprocessing system 110 are physically separate with one or morecomponents close to sensing element(s) of input device 100, and one ormore components elsewhere. For example, the input device 100 may be aperipheral coupled to a desktop computer, and the processing system 110may comprise software configured to run on a central processing unit ofthe desktop computer and one or more ICs (perhaps with associatedfirmware) separate from the central processing unit. As another example,the input device 100 may be physically integrated in a phone, and theprocessing system 110 may comprise circuits and firmware that are partof a main processor of the phone. In some embodiments, the processingsystem 110 is dedicated to implementing the input device 100. In otherembodiments, the processing system 110 also performs other functions,such as operating display screens, driving haptic actuators, etc.

The processing system 110 may be implemented as a set of modules thathandle different functions of the processing system 110. Each module maycomprise circuitry that is a part of the processing system 110,firmware, software, or a combination thereof. In various embodiments,different combinations of modules may be used. Example modules includehardware operation modules for operating hardware such as sensorelectrodes and display screens, data processing modules for processingdata such as sensor signals and positional information, and reportingmodules for reporting information. Further example modules includesensor operation modules configured to operate sensing element(s) todetect input, identification modules configured to identify gesturessuch as mode changing gestures, and mode changing modules for changingoperation modes.

In some embodiments, the processing system 110 responds to user input(or lack of user input) in the sensing region 120 directly by causingone or more actions. Example actions include changing operation modes,as well as GUI actions such as cursor movement, selection, menunavigation, and other functions. In some embodiments, the processingsystem 110 provides information about the input (or lack of input) tosome part of the electronic system (e.g., to a central processing systemof the electronic system that is separate from the processing system110, if such a separate central processing system exists). In someembodiments, some part of the electronic system processes informationreceived from the processing system 110 to act on user input, such as tofacilitate a full range of actions, including mode changing actions andGUI actions.

For example, in some embodiments, the processing system 110 operates thesensing element(s) of the input device 100 to produce electrical signalsindicative of input (or lack of input) in the sensing region 120. Theprocessing system 110 may perform any appropriate amount of processingon the electrical signals in producing the information provided to theelectronic system. For example, the processing system 110 may digitizeanalog electrical signals obtained from the sensor electrodes. Asanother example, the processing system 110 may perform filtering orother signal conditioning. As yet another example, the processing system110 may subtract or otherwise account for a baseline, such that theinformation reflects a difference between the electrical signals and thebaseline. As yet further examples, the processing system 110 maydetermine positional information, recognize inputs as commands,recognize handwriting, and the like.

“Positional information” as used herein broadly encompasses absoluteposition, relative position, velocity, acceleration, and other types ofspatial information. Exemplary “zero-dimensional” positional informationincludes near/far or contact/no contact information. Exemplary“one-dimensional” positional information includes positions along anaxis. Exemplary “two-dimensional” positional information includesmotions in a plane. Exemplary “three-dimensional” positional informationincludes instantaneous or average velocities in space. Further examplesinclude other representations of spatial information. Historical dataregarding one or more types of positional information may also bedetermined and/or stored, including, for example, historical data thattracks position, motion, or instantaneous velocity over time.

In some embodiments, the input device 100 is implemented with additionalinput components that are operated by the processing system 110 or bysome other processing system. These additional input components mayprovide redundant functionality for input in the sensing region 120, orsome other functionality. FIG. 1 shows buttons 130 near the sensingregion 120 that can be used to facilitate selection of items using theinput device 100. Other types of additional input components includesliders, balls, wheels, switches, and the like. Conversely, in someembodiments, the input device 100 may be implemented with no other inputcomponents.

In some embodiments, the input device 100 comprises a touch screeninterface, and the sensing region 120 overlaps at least part of anactive area of a display screen. For example, the input device 100 maycomprise substantially transparent sensor electrodes overlaying thedisplay screen and provide a touch screen interface for the associatedelectronic system. The display screen may be any type of dynamic displaycapable of displaying a visual interface to a user, and may include anytype of light emitting diode (LED), organic LED (OLED), cathode ray tube(CRT), liquid crystal display (LCD), plasma, electroluminescence (EL),or other display technology. The input device 100 and the display screenmay share physical elements. For example, some embodiments may utilizesome of the same electrical components for displaying and sensing. Asanother example, the display screen may be operated in part or in totalby the processing system 110.

It should be understood that while many embodiments of the invention aredescribed in the context of a fully functioning apparatus, themechanisms of the present invention are capable of being distributed asa program product (e.g., software) in a variety of forms. For example,the mechanisms of the present invention may be implemented anddistributed as a software program on information bearing media that arereadable by electronic processors (e.g., non-transitorycomputer-readable and/or recordable/writable information bearing mediareadable by the processing system 110). Additionally, the embodiments ofthe present invention apply equally regardless of the particular type ofmedium used to carry out the distribution. Examples of non-transitory,electronically readable media include various discs, memory sticks,memory cards, memory modules, and the like. Electronically readablemedia may be based on flash, optical, magnetic, holographic, or anyother storage technology.

GLOSSARY OF TERMS

The following Glossary of Terms is provided to define terms which areused herein. In addition to this Glossary of Terms, numerous Figures areprovided and described below in order to further illustrate and providean understanding of these and other terms used herein.

An “ohmic seam” is a break that provides an ohmic disconnect (a directcurrent open) between separated sensor electrodes, and is oftensubstantially perpendicular to an alignment axis of the separated sensorelectrodes. (“Substantially perpendicular” is used here to includeexactly perpendicular). For example, a “transmitter seam” is an ohmicseam that separates sets of transmitter electrodes, and the transmitterseam is often substantially perpendicular to an axis along which theseparated transmitter electrodes are aligned. Similarly, a “receiverseam” is an ohmic seam that separates sets of receiver electrodes, andthe receiver seam is often substantially perpendicular to an axis alongwhich the separated receiver electrodes are aligned. An ohmic seamtypically sections the sensor pattern in such a way that at least someof the transmitter electrodes and receiver electrodes in each section iswholly within their respective sections. As discussed further below, anohmic seam may or may not overlap a sensor electrode.

An ohmic seam may overlap and run along a sensor electrode that is notseparated by that ohmic seam. For example, a transmitter seam may runalong a multi-section receiver electrode that is electrically continuousacross the transmitter seam, such that this multi-section receiverelectrode belongs to multiple sections. The analogous is true forreceiver seams and transmitter electrodes. This arrangement typicallycreates split pixels (discussed below).

“Pitch” describes the spacing between sensor electrodes of a particulartype (e.g., transmitter electrodes or receiver electrodes). Pitch can bemeasured as a distance from center-to-center of adjacent sensorelectrodes of the same type.

“Opposite sensor electrodes” are substantially collinear sensorelectrodes of the same type which are disposed on different sides of anohmic seam. “Opposite transmitter electrodes” are transmitter electrodeswhich oppose one another across a transmitter seam, and “oppositereceiver electrodes” are receiver electrodes which oppose one anotheracross a receiver seam. Opposite sensor electrodes may have sensorelectrodes of another type or have conductive material that do not formsensor electrodes (e.g., conductive shields, routing lines, etc.)disposed between them. For example, opposite transmitter electrodes mayhave receiver electrode(s) and/or conductive strips held at systemground between them. Opposite sensor electrodes may be slightly offsetand not truly collinear, as long as they are at least partiallycollinear.

“Adjacent sensor electrodes” are substantially parallel, non-collinearsensor electrodes which have no other substantially parallel sensorelectrode of that type (e.g., another transmitter electrode or anotherreceiver electrode) disposed between them. Adjacent sensor electrodesmay have sensor electrodes, of another type or conductive material, thatdo not form sensor electrodes (e.g., conductive shields, routing lines,etc.) disposed between them. Adjacent sensor electrodes may be in thesame section of a sensor pattern, or be separated by a seam and be indifferent sections. Opposite sensor electrodes are not consideredadjacent sensor electrodes, even if they are offset from each other suchthat they are non-collinear.

“Pixel” is used to describe sensor pixels defined by the sensor patternand sensing scheme. A transcapacitive sensor electrode layout definesspaces of localized capacitive coupling between transmitter and receiverelectrodes, where the strength of that capacitive coupling variesmeasurably with the proximity of input objects. Those spaces oflocalized capacitive coupling are pixels of the transcapacitive sensor,and the change in the strength of capacitive coupling may be measured asa change in capacitance. Pixels are often associated with intersectionsbetween transmitter and receiver electrodes. “Intersection” is usedherein to include overlap without true contact. A transmitter electrodecan be capacitively coupled with more than one receiver electrode at apixel, and a receiver electrode can be capacitively coupled with morethan one transmitter electrode at a pixel.

An “undivided pixel” is a pixel where the localized capacitive couplingis dominated by the capacitive coupling of a single transmitterelectrode with a single receiver electrode.

A “split pixel” is a pixel where the localized capacitive coupling isdominated by the capacitive coupling of at least three sensor electrodes(e.g., two opposite transmitter electrodes and one receiver electrode,two opposite receiver electrodes and one transmitter electrode, or someother number and arrangement of transmitter and receiver electrodes).Split pixels may be found at some ohmic seams.

A “partial pixel” is a part of a split pixel that is associated with asubset of the sensor electrodes that form the split pixel. This subsetcapacitively couple with each other in a substantive way.

A “frame” is a snapshot of detected input (or lack thereof) in theentire sensing region. With a transcapacitive sensor, a frame may becomposed of measurements of the change in capacitance of the pixels.These measurements may be direct measurements of the capacitance, or maybe measurements of surrogates (e.g., voltage, current, charge, etc.).

The “frame period” is the time it takes to scan an entire sensing regionof a transcapacitive sensing input device. A frame period may be dividedinto separate time intervals. The “frame rate” (also “frame frequency”)is the inverse of frame period. The frame period and frame rate dependson factors such as how many transmitter electrodes there are and howlong it takes to scan each transmitter. Many applications require framerates above certain minimum rates.

Example Sensor Patterns with Ohmic Seams

Sensor patterns described herein are sectioned by ohmic seams betweensensor electrodes. These ohmic seams provide smaller sections that canenable improved performance as compared to a sensor patterns withoutohmic seams. That is, the sensor pattern is divided into multiplesections with sensor electrodes that are shorter than if the patternwere not divided. This sectioned approach may enable better performancesuch as faster frame rates, decreased susceptibility to noise, and thelike, when compared to an unsectioned sensor pattern. Also, the scanningof these smaller sections can be synchronized and sequenced in such away as to avoid or reduce imaging artifacts associated with the ohmicseam(s). It is appreciated that any of the sensor patterns describedherein may be utilized to implement any appropriate sensing region ofany appropriate input device, including sensing region 120 of inputdevice 100.

FIG. 2 shows a portion of an example capacitive sensor pattern 200 whichmay be used to implement a sensing region (e.g., sensing region 120),according to an embodiment. Capacitive sensor pattern 200 is used tointroduce some aspects that are generally applicable to all embodimentsdescribed herein. Specifically, capacitive sensor pattern 200 is for atranscapacitive input device and may be used to detect changes in mutualcapacitive coupling between a plurality of transmitter electrodes 250and a plurality of receiver electrodes 260. The plurality of transmitterelectrodes 250 overlap with and the plurality of receiver electrodes 260at a grid of intersections 270 (three intersections 270-1, 270-2, and270-3 are labeled in FIG. 2).

In sensor pattern 200, the pluralities of transmitter and receiverelectrodes 250, 260 are aligned horizontally and vertically,respectively. Other embodiments may align them in some other manner. Forexample, various embodiments may have overall sensor electrode alignmentdirections that are rotated from that of sensor pattern 200. As anotherexample, various embodiments may have different angles between theirsensor electrodes than that of sensor pattern 200; that is, pairs oftransmitter electrodes 250 or receiver electrodes 260 may not beparallel, and/or the plurality of transmitter electrodes 250 may not bealigned orthogonally to the plurality of receiver electrodes 260. As afurther example, various embodiments may have overall alignmentdirections that are rotated from that of sensor pattern 200 anddifferent angles between their sensor electrodes.

These pluralities of transmitter and receiver electrodes 250, 260 areshown as thin lines in FIG. 2, and they may be of any appropriatephysical shape in actuality. For example, various sensor electrodes maybe composed of entirely linear portions, entirely nonlinear portions, ora combination of linear and nonlinear portions. As another example,various sensor electrodes may have multiple parallel sections arrangedas tines or loops, multiple polygons linked in series, etc. Variousfigures in this application depict sensor electrodes that are simplerectangles, linked rectangles, and slotted rectangles. These shapes areused for convenience, and generally simple rectangles are used toprovide simpler figures for discussion.

The pluralities of transmitter and receiver electrodes 250, 260 may beformed of any appropriate stack-up of material. In some embodiments, thepluralities of transmitter and receiver electrodes 250, 260 are disposedon completely different conductive layers of material. For example, theplurality of transmitter electrodes 250 may be entirely formed in afirst layer of conductive material, the plurality of receiver electrodes260 may be entirely formed in a second layer of conductive material, anda dielectric material may separate these first and second layers. Asanother example, the plurality of transmitter electrodes 250 (or theplurality of receiver electrodes 260) may be formed from multiple layersof conductive material.

In some embodiments, the pluralities of transmitter and receiverelectrodes 250, 260 do share one or more conductive layers of material.For example, the plurality of transmitter electrodes 250 may be entirelyformed in a first layer of conductive material, and the plurality ofreceiver electrodes 260 may be partially formed in the first layer ofconductive material and partially formed in a second layer of conductivematerial. The first layer may contain distinct sensor elements of theplurality of receiver electrodes 260, and the second layer may containconductive jumpers that connect select sensor elements into completereceiver electrodes, or vice versa. Dielectric material may separate thejumpers from shorting with the plurality of transmitter electrodes 250where the jumpers intersect with that plurality. As another example, theplurality of transmitter electrodes 250 may be partially formed in afirst layer of conductive material and partially formed in a secondlayer of conductive material, and the plurality of receiver electrodes260 may be entirely formed in the second layer of conductive material.In various other examples, the plurality of transmitter electrodes 250(or the plurality of receiver electrodes 260) may be formed from morelayers of conductive material.

The sensor pattern may be designed such that the plurality of receiverelectrodes 260 is closer than the plurality of transmitter electrodes250 to where input objects are likely to be. For example, the pluralityof receiver electrodes 260 may be closer to an associated input surface.

The sensor pattern 200 may be physically implemented with anyappropriate materials. For example, the sensor electrodes may be formedof copper disposed in one or more layers of a FR4-type fiberglassreinforced epoxy laminated PCB. As other examples, the sensor electrodesmay be formed of other conductive materials, such as conductive ink(e.g., carbon ink, silver ink), ITO (indium tin oxide), conductivenano-particles, metal mesh, etc. Also, the sensor electrodes may bedisposed on an appropriate insulative material(s), such as glass,polyimide, polyester (e.g., PET, or polyethylene terephthalate), amongothers.

Not shown in FIG. 2, transmitter electrodes 250 and receiver electrodes260 are coupled with sensing circuitry (transmitter circuitry andreceiver circuitry, respectively) of a processing system such asprocessing system 110. In some embodiments, one or more of thetransmitter electrodes may be coupled to transmitter circuitry atmultiple locations. For example, TX1 may be coupled with sensingcircuitry on its first end and also on its second end; these couplingsmay allow charge to be placed on TX1 more quickly than if TX1 wascharged from only one end.

In FIG. 2, the spaces of localized capacitive coupling betweentransmitter and receiver electrodes are located about theirintersections. Thus, the centers of the pixels are located at theintersections of transmitter electrodes and receiver electrodes.

As will be discussed further below, along with alternatives, variousembodiments with sectioned sensor patterns may transmit in and scanmultiple sections in parallel (concurrently, such that multiple sectionswill transmit at the same time at least some of the time). This canreduce the number of time intervals during which transmitter electrodestransmit per frame, and increase the frame rate. Some embodiments usesensing schemes that reduce jitter (e.g., in positions detected forinput object(s)), detrimental effects from settling, cross-talk fromadjacent or opposite transmitter electrodes, etc. For example, in someembodiments, opposite transmitter electrodes may purposely be activatedat substantially overlapping time intervals, at partially overlappingtime intervals, or at non-overlapping time intervals. As anotherexample, some embodiments coordinate the scanning of two or moresections by coordinating transmitter signals, transmission times, and/oracquisition of resulting signals.

In some embodiments, portions of a processing system (e.g., processingsystem 110) collect separate values indicative of responsescorresponding to transmitter signals from each section, and thencentrally processes these centrally as a single larger image. Forexample, some embodiments comprise processing systems employing multipleICs; these ICs may scan the sections separately, and provide theirresults for central processing by a central controller. Depending on theimplementation, the central controller may be able to process theresults as if they were obtained from a single large section.

Further, some embodiments are physically configured to reducemeasurement artifacts that may occur near the ohmic seams. For example,some embodiments comprise seams designed such that the change incapacitance due to an input object is substantially the same for a pixelnear an ohmic seam and for a pixel away from any ohmic seams (e.g., inthe inner portion of each section). As another example, some embodimentsuse regular pitches and symmetric dimensions throughout the sensorpattern—near, away from, or at an ohmic seam. As yet another example,some embodiments use sensor patterns with small gaps between transmitterelectrodes at transmitter seams, and/or with small gaps between receiverelectrodes at receiver seams.

FIGS. 3-5 illustrate several examples of how a sensor pattern may bedivided into smaller sections by ohmic seams, according to variousembodiments. FIG. 3 shows a sensor pattern 300 that has been dividedinto two sections 301, 302 (halves are shown), by ohmic seam 305. FIG. 4shows a sensor pattern 400 that has been divided into three sections401, 402, 403 (thirds are shown) by ohmic seams 405 and 415. FIG. 5shows a sensor pattern 500 that has been divided into four sections 501,502, 503, 504 (fourths are shown) by perpendicularly intersecting ohmicseams 505 and 515. Other embodiments may have sensor patterns with othernumbers and arrangements of ohmic seams and sections. For example, anembodiments may have six sections divided by one transmitter seam andtwo receiver seams.

FIGS. 3-5 provide only three examples. It should be appreciated that anynumber of sections is permissible, and that sections may be of differentshapes and/or sizes. In some embodiments, the ohmic seams may or may notcorrespond to physical breaks in some of the sensor electrodes. Forexample, a transmitter electrode may lie on both sides of a receiverseam, and a receiver electrode may lie on both sides of a transmitterseam. This arrangement generally creates, along the ohmic seams, splitpixels comprised of partial pixels. Split pixels are further describedin conjunction with description of FIG. 8 and FIG. 9.

FIG. 6 shows the layout of an example four-section sensor pattern 600with sensor electrodes that are simple rectangles in shape. Transmitterelectrodes (TX) may be formed entirely in a first layer, receiverelectrodes (RX) may be formed entirely in a second layer, and theselayers are separated by a dielectric material. Transmitter seam 605separates sensor electrodes of sections 1 and 3 from the sensorelectrodes of sections 2 and 4, and provides an ohmic break between thetransmitter electrodes (TX) of those sections. Receiver seam 615separates sensor electrodes of sections 1 and 2 from the sensorelectrodes of sections 3 and 4, and provides an ohmic break between thereceiver electrodes (RX) of those sections. Together, the transmitterand receiver seams 605, 615 physically separate the transmitterelectrodes and receiver electrodes in each of the four sections (1, 2,3, 4) from the transmitter and receiver electrodes in the othersections. Transmitter seam 605 sections adjacent receiver electrodesRX3,1 and RX4,1 (and also RX1,1, and RX2,1) and separates oppositetransmitter electrodes. Receiver seam 615 sections adjacent transmitterelectrodes TX3,1 and TX1,1 (and TX4,1 and TX2,1) and separates oppositereceiver electrodes. Separate transmitter electrodes are labeled TXi,jand separate receiver electrodes are labeled RXi,j where i representsthe sensor section and j numbers the sensor electrode within thesection. The section and sensor electrode numbering are arbitrary. ThisTX, RX, i, and j notations and numbering schemes are utilized in othersensor patterns described herein in similar ways.

Circle 620 represents a pixel centered at the intersection of TX4,4 andRX4,4. (With other sensor electrode shapes or layouts, the pixels maynot be centered at the intersections of transmitter and receiverelectrodes). The circles, ovals, other indicators used herein torepresent pixels are meant to locate those pixels, and not meant to showthe space of that pixel. For example, circle 620 is meant to locate thatpixel in FIG. 6, and is not meant to be coextensive with the space ofthat pixel. Circles 621 and 622 do not represent pixels as they are notcentered at the center of localized spaces of capacitive couplingbetween transmitter and receiver electrodes in this example. Circle 630represents an example area associated with a finger touch to the sensorpattern 600 (often realized as a touch to an associated input surfacedisposed over the sensor pattern 600). As can be seen, a finger touch tothe sensor pattern 600 will typically affect the capacitive responses ofseveral pixels.

P_(TX) represents the transmitter electrode pitch. W_(TX) represents theeffective width of a transmitter electrode. P_(RX) represents thereceiver electrode pitch. W_(RX) represents the effective width of areceiver electrode. These four notations are used for analogousmeasurements in the other Figures. Sensor pattern 600, like the otherexamples shown in the figures, has a regular transmitter pitch and aregular receiver pitch. However, other embodiments may have variablepitches. Similarly, sensor pattern 600 has transmitter electrodes of thesame effective width and receiver electrodes of the same effectivewidth. However, other embodiments may have transmitter electrodes ofdifferent widths.

FIG. 6 shows opposite receiver electrodes that oppose one another acrossa single receiver seam (e.g., RX1,1 and RX3,1 opposite each other acrossreceiver seam 615), and not across multiple receiver seams. Similarly,FIG. 6 shows opposite transmitter electrodes that oppose one anotheracross a single transmitter seam (e.g., TX1,1 and TX2,1 oppose eachother across transmitter seam 605), and not across multiple transmitterseams. Although not required, opposite sensor electrodes are often trulycollinear with one another as they are in FIG. 6.

FIG. 6 also shows adjacent sensor electrodes. For example, RX3,3 andRX3,4 are adjacent receiver electrodes, and RX3,1 and RX 4,1 are alsoadjacent receiver electrodes. As another example, TX3,3 and TX3,4 areadjacent transmitter electrodes, and TX1,1 and TX3,1 are also adjacenttransmitter electrodes.

FIG. 6 shows both the transmitter and the receiver electrodes physicallyending at either type of seam, but this is not required. For example,transmitter electrodes can be physically contiguous across receiverseams. As another example, receiver electrodes can be physicallycontiguous across transmitter seams. Such contiguous layouts may producesplit pixels, which are discussed further below.

FIG. 6 shows an embodiment with both transmitter and receiver seams.However, embodiments need not have both transmitter and receiver seams.That is, some embodiments have transmitter seam(s) only, someembodiments have receiver seam(s) only, and some embodiments have bothtransmitter seam(s) and receiver seam(s).

FIG. 7 shows a layout of an example four-section sensor electrode sensorpattern 700 with sensor electrodes that are not merely simple rectanglesin shape, according to an embodiment. In sensor pattern 700, entiretransmitter electrodes (TX) are disposed in a first layer of conductivematerial. Also disposed in the first layer of material are sensorelements of receiver electrodes (RX). These sensor elements areconnected by conductive jumpers 730 (one jumper 730 is labeled in FIG.7) disposed in a second layer of conductive material. The jumpers areseparated from the transmitter electrodes by dielectric material (notshown).

Ohmic seam 705 is a transmitter seam and ohmic seam 715 is a receiverseam. Transmitter seam 705 separates the sensor electrodes of sections 1and 3 from the sensor electrodes of sections 2 and 4, and provides anohmic break between the receiver electrodes in those sections. Receiverseam 715 separates sensor electrodes of sections 3 and 4 from the sensorelectrodes of sections 1 and 2, and provides an ohmic break between thereceiver electrodes in those sections. Receiver seam 715 runs betweenTX1,1 and TX3,1, and between TX2,1 and TX4,1. Transmitter seam 705 runsbetween RX1,1 and RX2,1, and between RX3,1 and RX 4,1. Note that sensorpattern 700 does not have split pixels.

As illustrated by FIG. 7 and as also discussed above with FIG. 2, manyother types of sensor patterns and sensor electrode shapes arecontemplated with the embodiments described herein. In the sensorpattern 700, the transmitter and receiver electrodes are designed to bethinner at intersections, and have reduced overlap compared to if theywere not thinner at those intersections.

A pixel in sensor pattern 700 is located by circle 720, and is centeredabout the intersection of TX4,2 and RX4,2. Circles 721 and 722 seem tolocate centers of other pixels are first glance, but they do not. Thatis, although multiple sensor electrodes are near each other at circles721 and 722, these circles 721 and 722 do not locate centers of spacesof localized capacitive coupling between transmitter and receiverelectrodes. Instead, circle 721 is located between the centers of actualpixels: a first nearby pixel is located at the intersection of TX4,1 andRX4,2, and a second nearby pixel located at the intersection of TX2,1and RX2,2. Similarly, circle 722 is located between the centers ofactual pixels: a first nearby pixel is located at the intersection ofTX1,2 and RX1,1 and a second nearby pixel is located at the intersectionof TX2,2, and RX2,1.

FIGS. 8-9 illustrate example sensor patterns 800, 900 with split pixels,in accordance with some embodiments. Specifically, in each sensorpattern 800, 900, there is at least one ohmic seam that overlaps with asensor electrode; thus, the respective pluralities of transmitterelectrodes and receiver electrodes form a plurality of split pixelscoinciding with this at least one ohmic seam. FIGS. 8 and 9 both depictsplit pixels formed from three sensor electrodes each (one transmitterelectrode and two receiver electrodes for sensor pattern 800, and twotransmitter electrodes and one receiver electrodes for sensor pattern900). However, other sensor patterns may have split pixels formed withother numbers and ratios of transmitter or receiver electrodes.Similarly, FIGS. 8 and 9 both depict split pixels formed from twopartial pixels each. Other sensor patterns may have split pixels formedfrom other numbers of partial pixels.

The total response at a split pixel may be determined as a combinationof the responses at the partial pixels. For example, in one embodiment,the total response is computed as a simple sum of the responses of thepartial pixels from which it is constituted. As another example, in oneembodiment, the total response at a split pixel is computed as a scaledand/or weighted sum of the partial pixel responses. That is, a scalingand/or weighting is applied to at least one partial pixel that differsfrom the weight (considered one if not changed) of at least one otherpixel. This scaling or weighting may be based on an amount of signalamplification associated with said at least one partial pixel, on aconfiguration of the sensor electrodes forming the partial pixel, etc.

The scaling or weighting associated with the partial pixels may bedetermined at design, at manufacture, or after manufacturing (e.g.,during operation). For example, the capacitive interactions of thesensor electrodes and input objects may be modeled during design. Asanother example, the responses of the split pixels of a sensor devicemay be measured during manufacture. As a further example, the responsesof the split pixels may be measured in the field, during operation.Appropriate weights assigned to the partial pixels may be stored in amemory or some other portion of an associated processing system (seee.g., memory 1525 of processing system 1510, shown in FIG. 15).

FIG. 8 illustrates an example of a sensor pattern 800 that is dividedinto two sections (section 1, section 2) by a receiver seam 815,according to an embodiment. Receiver seam 815 overlaps and runs along atransmitter electrode TX1/2,0 that does not have an ohmic disconnect atthe receiver seam 815. That is, receiver seam 815 does not divideTX1/2,0 ohmically. The notation TX1/2,0 indicates that it is contiguousacross receiver seam 815, and is partially in section 1 and partially insection 2. Sensor pattern 800 illustrates a sensor pattern whichincludes undivided pixels such as undivided pixel 820 and split pixelssuch as split pixel 826. Undivided pixel 820 is located at theintersection of TX2,2 and RX2,5. The split pixels of pattern 800 eachconsists of a space of localized capacitive coupling dominated by threesensor electrodes—one transmitter electrode (TX1/2,0) and two receiverelectrodes. For example, split pixel 826 is made up of two partialpixels—one located at the intersection of TX1/2,0 and RX1,5 and onelocated at the intersection of TX1/2,0 and RX2,5.

FIG. 9 illustrates an example of a sensor pattern 900 that is dividedinto two sections (section 1, section 2) by a transmitter seam 905,according to an embodiment. In FIG. 9, each of the receiver electrodes(e.g., RX1,1) is composed of multiple parallel sections. Specifically,the receiver electrodes are each composes of two parallel sectionsconnected at both ends to each other, and has the general shape of aslotted rectangle. Transmitter seam 905 overlaps and runs along areceiver electrode RX1/2,0 that does not have an ohmic disconnect at theohmic seam. That is, transmitter seam 905 does not divide RX1/2,0ohmically. The notation of RX1/2,0 indicates that receiver electrodeRX1/2,0 is partially in section 1 and partially in section 2.

Sensor pattern 900 includes undivided pixels (e.g., circle 920represents an undivided pixel) and split pixels (e.g., circle 926represents a split pixel). The split pixels are formed from partialpixels, such as partial pixels represented by circle 924 located at theintersection of TX1,5 and RX1/2,0 and circle 925 located at theintersection of TX2,5 and RX1/2,0. In sensor pattern 900, each of thesplit pixels consists of a space of localized capacitive couplingdominated by three sensor electrodes—one receiver electrode (RX1/2,0)and two transmitter electrodes. For example, split pixel 926 is made upof two partial pixels located at the intersection of RX1/2,0 and TX1,1and at the intersection of RX1/2,0 and TX2,1.

As illustrated by the above described sensor patterns, variousembodiments have various sensor pattern layouts and sensor patternshapes. It should also be reiterated that various embodiments may differfrom those illustrated herein. For example, in some embodiments,transmitter seams (or receiver seams) are not perpendicular to analignment direction of the transmitter electrodes (or receiverelectrodes) that they divide. As another example, some embodiments havestraight transmitter electrodes that run vertically through the sensorpattern and straight receiver electrodes that run horizontally throughthe sensor pattern with the transmitter and receiver electrodes arrangedsubstantially perpendicular relative to one another. Similarly, someembodiments have straight transmitter electrodes that run horizontallyand straight receiver electrodes that run vertically with thetransmitter and sensor electrodes arranged substantially orthogonallyrelative to one another. As a further example, sensor electrodes may beof any appropriate shape, and a single sensor pattern may employtransmitter electrodes (or receiver electrodes) or different shapes andsizes. These sensor electrodes may be non-linear in part (piecewiselinear) or in whole (never linear), may not be parallel to other sensorelectrodes of the same type or perpendicular to sensor electrodes of adifferent type, or differ in other respects from what is depicted in theFigures.

Many other variations are possible and contemplated. For example, ohmicseams may not extend across the entire sensor pattern. As a specificexample, a sensor pattern with a receiver seam may have receiverelectrodes that extend partway across the sensor pattern to oppose eachother at that receiver seam; this sensor pattern may also have otherreceiver electrodes that extend across the entire sensor pattern and notintersect the receiver seam. The converse is also true for sensorpatterns with transmitter seams that extend partially across thosesensor patterns.

As another example, sensor patterns may have asymmetric sections. Thesections may differ in the number of sensor electrodes, the sizes ofsensor electrodes, the pitch of the sensor electrodes, and the like. Asa specific example, a sensor pattern with an odd number of transmitterelectrodes and a receiver seam may locate the receiver seam betweentransmitter electrodes (which would result in no split pixels at thereceiver seam) instead of over the transmitter electrode (which wouldlikely result in split pixels at the receiver seam).

Sensing Schemes

To scan sections and obtain frames of input information, the transmitterelectrodes are activated to transmit according to an appropriate sensingscheme. Various sensing schemes may be used to scan sectioned sensorpatterns, in accordance with various embodiments. For ease ofexplanation, example sensing schemes discussed here will often refer toFIG. 6 and sensor pattern 600. However, the sensing schemes discussedhere may be analogized for and applied to any appropriate sensor patternwith any number of sections. The following discussion also refers to theTXi,j notation introduced earlier, and introduces additionalmathematical notation for ease of explanation.

When a transmitter electrode is activated and driven to transmittransmitter signals, it is modulated with a transmitter signal (also“sensing signal”). When a transmitter electrode is not driven totransmit transmitter signals, it is not modulated with a transmittersignal; the transmitter electrode may be held at high impedance(electrically floating) or a constant voltage (such as a referencevoltage, system ground, or some other voltage).

The transmission sequence for a section may be described in amathematical way. During the time interval t which transmitterelectrodes transmit do not change (and where: t∈[n,n+1) and n is aninteger) an applicable output of a function Mi( ) may be used todescribe which transmitter electrodes (if any) are transmitting in theassociated i section during that time interval. For example, for a valuen, the output of Mi(n)=j indicates that transmitter TX(i,j) (transmitterj of section i) is transmitting during that time n. For various inputsand Mi( ), the output may be a scalar, a vector (indicating multipletransmitter electrodes concurrently transmitting in section i), or null(indicating no transmitter electrodes transmitting in section i) duringthe corresponding time intervals. For simplicity, it is assumed herethat the j numbering of sensor electrodes within a section is monotonic(with a possible exception for sensor electrodes that are contiguousacross a seam). In this way, Mi( ) provides a convenient way to expressa transmission pattern which maps a then-current time interval n towhich transmitter electrodes are transmitting in the i section duringthat time interval n.

Some embodiments divide their frame periods into uniform time intervalsthat are equal in time, some embodiments divide their frame periods intonon-uniform time intervals, and some embodiments allow the timeintervals to be uniform or non-uniform. For example, some embodimentsrequire potential changes to which transmitter electrodes aretransmitting to be equally spaced in time, and some embodiments do notimpose any such requirements regarding equal or unequal spacing in time.The lengths of the time intervals affect how long the transmitterelectrodes transmit.

An embodiment may use a transmission pattern that repeats in a sectionevery frame. This may be described by repeating the same Mi( ) functionfor the section(s) for every frame. An embodiment may use a transmissionpattern that repeats in a section at a multiple of frames. This may bedescribed by repeating a sequence of different Mi( ) functions for thesection. An embodiment may use an aperiodic transmission pattern thatdoes not repeat over any multiple of frames. This may be described witha non-repeating sequence of different Mi( ) functions.

Some embodiments use sensing schemes in which each section has atransmission pattern described by a same Mi( ) function. That is, Mi()=a same M₀( ) for all i. Transmission patterns are related if they areidentical on the same time basis, identical but shifted in time,mirror-symmetric, have other symmetry, and the like. Some embodimentsuse sensing schemes in which each section has a transmission patterndescribed by a different Mi( ) function. That is, no two sections haverelated transmission patterns. Some embodiments use sensing schemes inwhich some of the sections have transmission patterns described by asame Mi( ) function and some of the sections have transmission patternsdescribed by different Mi( ) functions. That is, some of the sectionshave related transmission patterns and some of the sections do not haverelated transmission patterns.

Some embodiments concurrently transmit with transmitter electrodes ofdifferent sections. That is, these embodiments scan different sectionsin parallel by transmitting with different transmitter electrodes inthose sections at the same time. In various embodiments, thiscorresponds to concurrently transmitting a first transmitter signal witha first transmitter electrode disposed on a first side of an ohmic seam,and a second transmitter signal with a second transmitter electrodedisposed on a second side of the ohmic seam. The first transmittersignal and the second transmitter signal may be identical or differentsignals. Where this ohmic seam is a transmitter seam, the firsttransmitter electrode and the second transmitter electrode may beopposite transmitter electrodes (or be non-opposite transmitterelectrodes). Where this ohmic seam is a receiver seam, the firsttransmitter electrode and second transmitter electrode may not benon-adjacent sensor electrodes (or be adjacent transmitter electrodes).

Transmitter electrodes “concurrently transmit” when theycontemporaneously cause resulting signals in receiver electrodes. Thus,concurrently transmitting transmitter electrodes may transmit during asame time period, or during different time periods that overlap witheach other. For example, a first transmitter electrode may transmit afirst transmitter signal during a first time period and a secondtransmitter electrode may transmit a second transmitter signal during asecond time period. The first and second transmitter electrodesconcurrently transmit these first and second transmitter signals if thefirst and second time periods at least partially overlap each other, andif the effects that these first and second transmitter signals have onassociate receiver electrodes occur at the same time.

As a specific example of a sensing scheme with concurrent transmission,some embodiments concurrently transmit with multiple transmitterelectrodes, where each transmitter electrode is disposed in a differentsection. As another specific example of a sensing scheme with concurrenttransmission, some embodiments concurrently transmit with transmitterelectrodes separated from each other by receiver seams. As yet anotherspecific example of a sensing scheme with concurrent transmission, someembodiments concurrently transmit with opposite transmitter electrodes.Where there are multiple transmitter seams such that one transmitterelectrode opposes multiple other transmitter electrodes, some or all ofthese transmitter electrodes may transmit concurrently.

Transmitting in multiple sections concurrently (also called “parallelscanning”) allows entire sensor patterns to be scanned more quickly thannot transmitting in multiple sections concurrently (without parallelscanning, such as with “serial scanning”).

As noted above, some embodiments transmit with multiple transmitterelectrodes of a section concurrently, such that at least one receiver inthat section receives a mixed response. That is, at least one receiverelectrode receives a resulting signal that combines responsescorresponding to multiple transmitter signals concurrently transmittedby multiple transmitter electrodes in that section. Concurrentlytransmitting with multiple transmitter electrodes of a section may offerimproved noise resistance and use more power. This may be described byMi( ) functions that output vectors (indicating many transmitterelectrodes) for one or more inputs n.

As a specific example, in some embodiments, a first transmitterelectrode in a section transmits concurrently with a second transmitterelectrode in that section. The first transmitter electrode transmits afirst transmitter signal, and the second sensor electrode transmits asecond transmitter signal. If the first transmitter signal and thesecond electrical produce mathematically independent responses, theconcurrent transmissions produces resulting signals that may be used indetermining independent results associated with these responses (e.g., afirst result associated with a first response, and a second resultassociated with a second response, where the first and second responsescorrespond to the first and second transmitter signals, respectively.)

Some embodiments use sensing schemes where, at a particular time,multiple sections have transmitter electrodes transmitting, and at leastone of those sections have multiple transmitter electrodes transmitting.

Some embodiments use sensing schemes that comprise transmitting in asequence spatially moving relative to an ohmic seam. In a first exampleembodiment with a receiver seam, the transmission sequence starts closerto the receiver seam and moves away from said receiver seam. In a secondexample embodiment with a receiver seam, the sequence starts away fromthe receiver seam and moves toward the receiver seam. These sequencescorrespond to the following transmission relationship. First, a firsttransmitter electrode disposed on a first side of a receiver seamtransmits a first transmitter signal and a second transmitter electrodedisposed on a second side of the receiver seam transmits a secondtransmitter signal. Second, a third transmitter electrode transmits athird transmitter signal after the first transmitter electrode transmitsthe first transmitter signal, and a fourth transmitter electrodetransmitting a fourth transmitter signal after the second transmitterelectrode transmits the second transmitter signal. In the first exampleembodiment, the third transmitter electrode is disposed on the firstside of the receiver seam and is farther from the receiver seam than thefirst transmitter electrode, and the fourth transmitter electrode isdisposed on the second side of the receiver seam and is farther from thereceiver seam than the second transmitter electrode. In the secondexample embodiment, the third transmitter electrode is disposed on thefirst side of the receiver seam and is closer to the receiver seam thanthe first transmitter electrode, and the fourth transmitter electrode isdisposed on the second side of the receiver seam and is closer to thereceiver seam than the second transmitter electrode. In both cases, thefirst transmitter signal may or may not be transmitted concurrently withthe second transmitter signal, and the third transmitter signal may ormay not be transmitted concurrently with the fourth transmitter signal.

The following is one specific example of a sensing scheme with a spatialsequence starting from closer to a seam and moving away from the ohmicseam. In an example embodiment, a sensing scheme may be described with asame Mi( ) for all sections, where Mi(n)=(n modulo N)+1, and where N isthe total number of transmitter electrodes in the i section and n is aninteger from 0 to N−1, inclusive. For sensor pattern 600, N=4, and nvaries from 0 to 3. With the sensor pattern 600, this sensing schememeans that: 1) opposite transmitter electrodes transmit concurrently andduring the same time periods; and 2) the transmission sequence starts atreceiver seam 615, in the middle of sensor pattern 600 and moves awayfrom the receiver seam 615, outwards toward the transmitter electrodesat the edges of sensor pattern 600. That is, with this Mi(n)=(n moduloN)+1 descriptive of all of the sections of sensor pattern 600 in anembodiment, the following is true of this embodiments' transmissionsequence: TX1,1, TX2,1, TX3,1, and TX4,1 transmit during an initial timeinterval (interval 1), TX1,2, TX2,2, TX3,2, and TX4,2 transmit duringthe next time interval (interval 2), TX1,3, TX2,3, TX3,3, and TX4,3transmit during the next time interval (interval 3), and TX1,4, TX2,4,TX3,4, and TX4,4 transmit during the next time interval (interval 4). Insome embodiments where the same Mi( ) is repeated in the next frameperiods, after the last time interval, the transmission sequencerepeats, and starts over again at the receiver seam 615, from the middleof the sensor pattern 600.

The following is one specific example, in reference to sensor pattern600, of a sensing scheme with a spatial sequence starting from closer toa seam and moving away from the ohmic seam for at least one section, andstarting from farther from the ohmic seam and moving closer to the ohmicseam for at least one other section. This example uses the sections toemulate a set of similarly oriented, distinct sensor devices. Thesections have transmitter sequences that are identical relative to aglobal reference, and not a local reference such as an ohmic seam. Inthis example, the following transmitter electrodes transmit during thespecified time intervals, and other transmitter electrodes do not.During a first time interval, TX1,4, TX2,4, TX3,1, and TX4,1 transmit.During a second time interval, TX1,3, TX2,3, TX3,2, and TX4,2 transmit.During a third time interval, TX1,2, TX2,2, TX3,3, and TX4,3 transmit.During a fourth time interval, TX1,1, TX2,1, TX3,4, and TX4,4 transmit.These four time intervals complete the frame period, and the sequencemay repeat, reverse, or change in some other way. In some embodiments,sections 2 and 4 are not scanned in parallel with and/or in the samesequence as sections 1 and 3.

Some embodiments use sensing schemes that do not transmit in (and thusnot scan) one or more sections during part of the frame period. Forexample, some embodiments may transmit in a section during a first partof a frame period, and not transmit in that section during a second partof that frame period. As a specific example, a sensing scheme that canbe used with sensor pattern 600 is as follows. During a first part of aframe period, the embodiment transmits in sections 1 and 3 in similar ordifferent ways, and does not transmit in sections 2 and 4. Then, duringa second part of the frame period immediately following the first partof the frame period, the embodiment transmits in sections 2 and 4 insimilar or different ways (which may be similar or different with thetransmission pattern of sections 1 or 3). Then, the embodiment repeatsthis sequence for additional frames. That is, it retransmits withsections 1 and 3 (and not sections 2 and 4) and then retransmits withsections 2 and 4 (and not sections 1 and 3) in a similar manner, and soon.

Below is another specific example of such a sensing scheme. Withreference to sensor pattern 600, during a first part of a frame period,sections 1 and 2 transmit and sections 3 and 4 do not. Specifically, thefollowing transmitter electrodes transmit during sequential timeintervals of that frame period, and other transmitter electrodes do nottransmit. TX1,4 and TX2,4 transmit during a first time interval (timeinterval 1). TX1,3 and TX2,3 transmit during the next time interval(time interval 2). TX1,2 and TX2,2 transmit during the next timeinterval (time interval 3). TX1,1 and TX2,1 transmit during the nexttime interval (time interval 4). TX3,1 and TX4,1 transmit during thenext time interval (time interval 5). TX3,2 and TX4,2 transmit duringthe next time interval (time interval 6). TX3,3 and TX4,3 transmitduring the next time interval (time interval 7). TX3,4 and TX4,4transmit during the next time interval (time interval 8). This sequencecan repeat, reverse, or change in some other way for additional timeintervals, depending on the sensing scheme. For example, in someembodiments, after the frame period has ended, the sequence starts overagain with TX1,4 and TX2,4 transmitting.

It can be seen from the transmission sequences discussed above that someembodiments do not concurrently transmit with adjacent transmitterelectrodes on different sides of a receiver seam. For example, invarious embodiments, adjacent transmitter electrodes across a receiverseam do not transmit concurrently. Opposite transmitter electrodes mayor may not transmit concurrently. In one example of such a transmissionsequence, and in reference to sensor pattern 600, TX1,1 and TX2,1 bothtransmit (and TX3,1 and TX4,1 do not transmit) during a first timeinterval, and TX3,1 and TX4,1 transmit (and TX1,1 and TX2,1 do nottransmit) during the next time interval.

The following is a specific example described with continued referenceto FIG. 6, the following transmitter electrodes transmit duringsequential time intervals of a frame period and other transmitterelectrodes do not transmit. During at a first time interval, TX1,4,TX2,4, TX3,4, and TX4,4 transmit. During a second time interval that isthe next time interval, TX1,3, TX2,3, TX3,3, and TX4,3 transmit. Duringa third time interval that is the next time interval, TX1,2, TX2,2,TX3,2, and TX4,2 transmit. During a fourth time interval that is thenext time interval, TX3,1 and TX4,1 transmit. During a fifth timeinterval that is the next time interval, the TX1,1 and TX2,1 transmit.This frame period for sections having four transmitter electrodes eachthus comprises five time intervals. After this, the sequence may startover and repeat. It is appreciated that this scan sequence starts fromaway from the receiver seam 615 (e.g., at the edges of the sensorpattern), and moves toward receiver seam 615. Other sensing schemes maycomprise scan sequences that start at the receiver seam 615, and moveaway from the receiver seam 615 (e.g., towards the edges of the sensorpattern). For example, a reverse of the transmission sequence above maybe used. That is, and in reference to FIG. 6, and a first time intervalmay involve transmission with TX1,1 and TX2,1, a second time intervalmay involve transmission with TX3,1 and TX4,1, a third time interval mayinvolve transmission with TX1,2, TX2,2, TX3,2, and TX4,2 and so on.

It can also be seen from the transmission sequences discussed above thatsome embodiments concurrently transmit with transmitter electrodes onlyduring part of the frame period. For example, some embodiments havesections separated by a receiver seam. When a transmitter electrode verynear the receiver seam (e.g., right next to the receiver seam) istransmitting in one section, no transmitter electrodes in a section onthe other side of the receiver seam will transmit. By way of example,and in reference to FIG. 6, during a time interval when TX1,1 transmitsin Section 1, no transmitter electrodes in Section 3 (which is acrossreceiver seam 615 from Section 1) transmit. This may be carried totransmitter electrodes also separated by a transmitter seam. Further inreference to FIG. 6, in one embodiment, TX1,1 transmits in Section 1during a time interval when no transmitter electrodes in either Section3 or Section 4 transmit.

Some embodiments utilize sensing schemes that suspend transmissionsduring one or more non-transmitting time intervals (also “quiet timeintervals”) of the frame period. For example, some sensing schemesutilize quiet time intervals within frames and/or between frames, duringwhich no transmitter electrode transmits (all transmitter electrodes TXare not transmitting). Including time periods with suspendedtransmissions may be for any number of reasons, such as for interferencedetection or to decrease cross-talk.

In terms of interference detection, some embodiments receive on one ormultiple receiver electrodes during the quiet time intervals. Since thetransmitter electrodes do not transmit during the quiet time intervals,the signals received by the receiver electrodes correspond tointerferences (e.g., from the environment).

In terms of decreasing cross-talk, in some embodiments, there is atrade-off between the amount of time spent transmitting with aparticular transmitter to achieve improved signal-to-noise ratio (SNR)versus a higher frame rate. This may be due to a variety of factors.Example factors include the transient response of any kind of filteringthat may occur in transmission or reception. In some embodiments, theframe rate is set in such a way that the time interval may be too shortto allow effects as any filtering effects to settle out completely(e.g., to the level of noise, to some level set by specificationrequirements, etc). Thus, a residual left over from an earlier timeinterval (e.g., time interval k) can affect a measurement made for alater time interval (e.g., time interval k+1). In many embodiments, thisbecomes even more noticeable at the transition from the end of one frameto the beginning of the next. Such residual information can have theeffect of causing erroneous sensing. For example, an input objectlocated at a receiver seam may interact with a first transmitterelectrode on a first side of the receiver seam that transmits duringtime interval k, and with a second transmitter electrode on a secondside of the receiver seam that transmits during time interval k+1. Thisinput object may be detected as being located at the edge of the sensor,have a non-uniform impact across seams relative to interiors of sectionsand cause errors in position determinations, etc. Utilizing one or morequiet time interval(s) at the beginning and/or end of a frame period canreduce the detrimental effects of numerous such issues.

It is appreciated that many sensing schemes with different transmissionpatterns are possible and contemplated, including those which utilizeone or more quiet time intervals per frame period. For example, any ofthe sensing schemes described herein may have one or more quiet timeintervals added to it; these added quiet time interval(s) may be thefirst time interval, the last time interval, an intermediate timeintervals, or a combination thereof. As a specific example, one quiettime interval may be added at the end of a frame period, beforeadditional frame scans occur.

In one example embodiment, a transmission pattern with a quiet timeinterval begins with transmitter electrode(s) located at a receiver seamtransmitting and proceeds with a transmitter pattern moving spatiallyaway from the receiver seam (e.g., outward toward the edges of a sensorpattern). For example, with continued reference to FIG. 6, in oneembodiment, the following transmitter electrodes transmit during timeintervals of a frame period and other transmitter electrodes do nottransmit. During a first time interval, no transmitter electrodestransmit. During a second time interval immediately following the firsttime interval, TX1,1 transmits. During a third time interval immediatelyfollowing the second time interval, TX3,1 transmit. During a fourth timeinterval immediately following the third time interval, TX1,2 and TX3,2transmit. During a fifth time interval immediately following the fourthtime interval, TX1,3 and TX3,3 transmit. During a sixth time intervalimmediately following the fifth time interval, TX1,4 and TX3,4 transmit.This results in six time intervals to scan two sections having fourtransmitter electrodes each. Section 2 and/or section 4 may be scannedin parallel with the scanning of sections 1 and 3. After this, thesequence may start over. Or, if sections 2 and 4 were not scanned inparallel with sections 1 and 3, they may be scanned next.

Some embodiments reduce or prevent artifacts near receiver seams bysynchronizing opposite transmitter electrodes. Some embodiments tightlysynchronize opposite transmitter electrodes. That is, some embodimentstransmit, with opposite transmitter electrodes, transmitter signals ofsubstantially the same phase, amplitude, waveform shape, and/orfrequency (or with a phase, amplitude, waveform shape, and/or frequencyrelationship that is substantially constant from frame to frame), andalso begin and end transmission at substantially the same time. Thisapproach may help reduce signal degradation near a receiver seam. As onespecific example, and in reference to FIG. 6, in one embodiment,transmitter electrodes meeting at the transmitter seam 605 aresynchronized to transmit in the same phase and during the same timeinterval (e.g., TX1,4 and TX2,4).

Sensing schemes involving sensor patterns with split pixels are, in manyembodiments, similar to those which have been previously described. Forexample, the transmission pattern may mean transmitting in a wayspatially moving towards or away from an ohmic seam. As other examples,the transmission pattern may involve concurrently transmitting onopposite transmitter electrodes or include quiet time intervals. As afurther example, transmitter electrodes that are adjacent to each otherand on opposite sides of a seam may transmit at different times.However, where the split pixel involves a receiver seam that overlapsand runs along a transmitter electrode, no set of transmitter electrodesare adjacent to each other and are on opposite sides of this seam.

Coded Transmissions

Where a sensing scheme involves concurrent transmission with multipletransmitter electrodes, some or all of these multiple transmitterelectrodes may transmit transmitter signals that are uniquely coded. Forexample, the transmitter signals may conform to a variety of differentmodulation codes, including codes such as Walsh codes Hadamard codes,and pseudo-random sequences. The codes may also be of any appropriatelength. The transmitter signals may express the codes in any appropriateway, such as through differences in frequency, amplitude, phase, etc.For example, some embodiments differently modulate the frequencies ofconcurrent transmissions, and appropriately demodulate the receivedresulting signals to obtain independent results. Each independent resultis associated with a response corresponding to one of the concurrenttransmissions. FIGS. 10-12 show examples of specific multi-sectionedsensor patterns along with specific example sensing schemes havingcoding patterns, according to various embodiments. Other implementationsmay have different sensor patterns and/or other coding patterns.

In FIGS. 10-12, the sensing schemes with coding patterns are shown as atable. The columns indicate different sequential time intervals (e.g.,t1, t2, etc.). The rows contain coding states for their respectivelyaligned transmitter electrodes. A “+” symbol in table means that thetransmitter signal transmitted by the corresponding transmitterelectrode during that time interval has a first value for the encodingcharacteristic. In contrast, a “−” symbol in the table means that thetransmitter signal transmitted by the corresponding transmitterelectrode during that time interval has a second value for the encodingcharacteristic. An empty box means no transmitter signal is beingtransmitted.

For example, some embodiments modulate transmitter electrodes with aperiodic waveform when transmitting. Example periodic waveforms includesquare waves, saw tooth waves, triangle waves, sinusoids, combinationsthereof, more complex waveforms, etc. Where phase as the encodingcharacteristic for such embodiments, a “+” means that the transmittertransmits with the applicable waveform at a first phase, and a “−”symbol indicates that the transmitter transmits with the applicablewaveform at a second phase. In one embodiment, the first and secondphases are 180 degrees apart. In other embodiments, other phasedifferences are utilized.

FIG. 10 shows a sensor pattern 1000 that is divided into two sections(section 1, section 2) by a receiver seam 1015. A plurality oftransmitter electrodes and receiver electrodes are illustrated. Sensingscheme 1075 illustrates one example coding pattern which may be usedwith sensor pattern 1000. Specifically, sensing scheme 1075 involvesconcurrent transmission, according to a Hadamard code of length 4, withall four transmitter electrodes of section 2 concurrently transmittingduring sequential time intervals t1 to t4. Sensing scheme 1075 furtherinvolves concurrent transmission, according to the same Hadamard code oflength 4, with all four transmitter electrodes of section 1 duringsequential time intervals t5 to t8.

In FIG. 10, the top row of sensing scheme 1075 indicates that atransmitter signal having a first value for the encoding characteristicis transmitted on TX2,4 during time interval t1, that a transmittersignal having a second value for the encoding characteristic istransmitted on TX2,4 during time intervals t2-t4, and that TX2,4 doesnot transmit during time intervals t5-t8. For example, TX2,4 maytransmit with a waveform at a first phase during time interval t1, andtransmit with the waveform at a second phase during time intervalst2-t4, and not transmit during time intervals t5-t8. Other rows sensingscheme 1075 may be interpreted in a similar fashion. That is, TX2,3transmits with a transmitter signal having the second value for theencoding characteristic during time intervals t1, t3, and t4, transmitswith the transmitter signal having the first value for the encodingcharacteristic during time interval t2, and does not transmit duringtime intervals t5-t8. And, TX2,2 transmits with a transmitter signalhaving the second value for the encoding characteristic during timeintervals t1, t2, and t4, transmits with the transmitter signal havingthe first value for the encoding characteristic during time interval t3,and does not transmit during time intervals t5-t8. And, TX2,1 transmitswith a transmitter signal having the second value for the encodingcharacteristic during time intervals t1-t3, transmits with thetransmitter signal having the first value for the encodingcharacteristic during time interval t4, and does not transmit duringtime intervals t5-t8. Similarly, sensing scheme 1075 indicates thecoding for TX1,1, TX1,2, TX1,3, and TX1,4.

Sensing scheme 1075 depicts one embodiment where there is no concurrenttransmission with transmitter electrodes in section 1 and section 2 ofsensor pattern 1000. However, other embodiments of a sensing scheme witha coding pattern may have concurrent transmission with transmitterelectrodes of different sections. For example, an embodiment may havethe same sensor pattern 1000, use the same length 4 codes as those ofsensing scheme 1075, but concurrently transmit with all eighttransmitter electrodes for four time intervals (instead of concurrentlytransmitting with the four transmitter electrodes of section 1 for fourtime intervals and concurrently transmitting with the four transmitterelectrodes of section 2 for four other time intervals).

FIG. 11 shows sensor pattern 1000 with a different sensing scheme 1175having fewer time intervals than sensing scheme 1075 of FIG. 10. In FIG.11, the top row of sensing scheme 1175 indicates that a TX2,4 transmitsa transmitter signal having a first value for the encodingcharacteristic during time interval t1, that TX2,4 transmits atransmitter signal having a second value for the encoding characteristicduring time interval t2, and that TX2,4 does not transmit during timeintervals t3-t4. For example, during time interval t1, TX2,4 maytransmit with a waveform of a first phase, and during time interval t2,TX2,4 may transmit with a waveform of a second phase. Other rows ofsensing scheme 1175 may be interpreted in a similar fashion. Sensingscheme 1175 depicts one embodiment with concurrent transmission withtransmitter electrodes in sections 1 and 2 of sensor pattern 1000.

FIG. 12 shows a sensor pattern 1200 that is divided into two sections(section 1, section 2) by a receiver seam 1215, along with a sensingscheme 1275. In FIG. 12, the top row of sensing scheme 1275 indicatesthat a TX2,6 transmits a transmitter signal having a first value duringtime intervals t1-t4 and does no transmit during time intervals t5-t6.For example, T2,6 may transmit a transmitter signal with a waveform of afirst phase during time intervals t1-t4 and not transmit during timeintervals t5-t6. Other rows of sensing scheme 1275 may be interpreted ina similar fashion. Sensing scheme 1275 depicts concurrent driving oftransmitter electrodes in sections 1 and 2 of sensor pattern 1200.Sensing scheme 1275 also uses different code lengths (code lengths fourand two) and code types. The four rows identified by bracket 1276represent a 4×4 Walsh type of Hadamard coding. The two rows identifiedby bracket 1277 represent an orthogonal 2×2 coding, as do the two rowsidentified by bracket 1278. The four rows identified by bracket 1279represent a 4×4 Non-Walsh type of Hadamard coding. Thus, sensing scheme1275 also highlights that different code types and code lengths may beused within a sensing scheme.

Use of One or Multiple Integrated Circuits with a Sensor Pattern

One or multiple integrated circuits (ICs) may be utilized with asectioned sensor pattern of an input device, such as input device 100,according to some embodiments. The one or multiple ICs may each comprisean application-specific integrated circuit (ASIC) or be a generalpurpose integrated circuit.

In embodiments with a single IC, this single IC may be configured tooperate the sensor electrodes to acquire an image of input (or lackthereof) in the associated sensing region. The single IC may also beconfigured to perform further processing on the image, provide the imageto another processor (such as the CPU of an electronic system), etc.

In embodiments with multiple ICs, individual ICs may be configured toperform similar or different functions. For example, some embodimentscomprise multiple sensor electrode ICs (SEICs) that are configured to becommunicatively coupled to different sets sensor electrodes. These SEICsmay be communicatively coupled to (and perhaps be configured to operate)only transmitter electrodes, only receiver electrodes, or a combinationof transmitter and receiver electrodes. Similarly, these SEICs may becommunicatively coupled to sensor electrodes of only one section, tosensor electrodes that are contiguous across an ohmic seam, or todifferent sensor electrodes of multiple sections. Some multi-ICembodiments may comprise additional ICs that are communicatively coupledto the SEICs, and perform other functions than direct operation of thesensor electrodes.

FIGS. 13-14 shows some embodiments with multiple integrated circuits.FIG. 13 shows a portion of an input device 100B. Input device 100B usesa four-sectioned sensor pattern 1300. In one embodiment, sensor pattern1300 is similar or identical to sensor pattern 600 of FIG. 6. Inputdevice 100B comprises multiple sensor electrode integrated circuits(SEICs 1-4), each of which is communicatively coupled to all of thetransmitter and receiver electrodes of a section. Arrows 1311, 1321,1331, and 1341 indicate routing lines from SEICs 1, 2, 3, and 4 to thetransmitter electrodes of sections 1, 2, 3, and 4, respectively.Similarly, arrows 1312, 1322, 1332, and 1342 indicate routing lines fromthe receiver electrodes of sections 1, 2, 3, and 4 to SEICs 1, 2, 3, and4, respectively. Input device 100B further comprises a centralcontroller 1310, which may comprise one or multiple IC(s). Centralcontroller 1310 is utilized to coordinate SEICs 1-4, analyze theinformation received from SEICs 1-4 about input in the sensing region,and communicate with other components as appropriate. For example,central controller 1310 may coordinate the sensing scheme for inputdevice 100B. As another example, central controller 1310 may receiveresponses from SEICs 1-4 that correspond to the different transmittersignals, scale them as appropriate, and compile them into a singleimage. The central controller 1370 may perform further processing on theimage, and/or provide the image to another processor, such as the CPU ofan electronic system (not shown).

In FIG. 14, an input device 100C is shown. Input device 100C comprises a4-sectioned sensor pattern 1400 communicatively coupled with six SEICs(SEICs 1-6) (rather than the four SEICs shown in input device 100B ofFIG. 13). In one embodiment, sensor pattern 1400 is similar or identicalto sensor pattern 600 of FIG. 6. SEICs 5 and 6 are shared betweensections (e.g., sections 1 and 2 share SEIC 5 and sections 3 and 4 shareIC 6). In input device 100C, each of SEICs 1-4 is communicativelycoupled to all of the transmitter electrodes, and some of the receiverelectrodes, of a section. In contrast, SEICs 5-6 are receiver integratedcircuits that communicatively couple only to receiver electrodes.Specifically, SEIC 5 is communicatively coupled to some receiverelectrodes of sections 1 and 2, and SEIC 6 is communicatively coupled tosome receiver electrodes of sections 3 and 4. Arrows 1411, 1421, 1431,and 1441 indicate routing lines from ICs 1, 2, 3, and 4 to thetransmitter electrodes of sections 1, 2, 3, and 4, respectively.Meanwhile, arrows 1412, 1422, 1432, 1442, 1452, and 1462 indicaterouting lines from sensor electrodes to SEICs: from section 1 to SEIC 1,section 2 to SEIC 2, section 3 to SEIC 3, section 4 to SEIC 4, sections1 and 2 to SEIC 5, and sections 3 and 4 to SEIC 6. Input device 100Cfurther comprises a central controller 1410, which may comprise one ormultiple IC(s). Central controller 1410 is utilized to coordinate SEICs1-6, analyze the information received from SEICs 1-6 about input in thesensing region, and communicate with other components as appropriate

Some embodiments with multiple ICs partition the processing forconverting received resulting signals into input information among thosemultiple ICs. For example, input device 100B of FIG. 13 may split thesignal-to-input information processing among SEICs 1-4 and centralcontroller 1310 of input device 100B. These ICs may split the followingresponsibilities (if applicable to the system) in any variety of ways:storing a baseline reading, weighting or scaling, signal conditioning,choosing a sensing frequency, coordinating transmission patterns, signalprocessing, determining positional information, applying ballistics,recognizing gestures, controlling sleep and wake-up input device 100B,and communicating with a component outside of input device 100B, such asa host PC.

Some embodiments with multiple ICs synchronize these ICs. This canimprove performance, such as by reducing potential artifacts introducedby ohmic seams or multiple ICs. For example, some embodiments include acommon clock so that all ICs coupled to the common clock aresynchronized. The common clock can be used, for example, to ensure thatthe transmitter signals used by the ICs are all at the same frequency,or that the receiver electrodes all operate during the proper periods.This synchronization can reduce beat frequencies that result fromdestructive interference; these beat frequencies can be result inmistaken input. In various embodiments, a common clock can be obtainedby having one IC drive its clock signal out, and having other ICsreceive the clock signal. For example, with respect to FIG. 13,controller 1310 or any of SEICs 1-4 may provide this clock signal.Further, controller 1310 may provide a synchronization signal toinitiate the scanning of new frame, and further synchronize the ICs.

Example Processing System

FIG. 15 illustrates an example of a processing system 1510, which may beutilized with an input device, according to various embodiments.Processing system 1510 may be an implementation of processing system 110of input device 100. Other processing systems may be similarlyimplemented. In one embodiment, processing system 1510 is configured tobe communicatively coupled with a plurality of transmitter electrodesand a plurality of receiver electrodes (such as those illustrated invarious Figures). Processing system 1510 includes transmitter circuitry1505 and receiver circuitry 1515. In various embodiments, transmittercircuitry 1505 is located in one or multiple ICs. That is, in someembodiments, transmitter circuitry 1505 is located entirely in a singleIC; and, in some embodiments, transmitter circuitry 1505 is located inmultiple ICs. Similarly, in various embodiments, receiver circuitry 1515may comprise portions of one or multiple ICs. The ICs implementingtransmitter circuitry 1505 may or may not also implement receivercircuitry 1515. That is, the relevant IC may include only receivercircuitry, only transmitter circuitry, or some receiver circuitry andsome transmitter circuitry. Some embodiments additionally include one ormore of the following: memory 1525, analysis circuitry 1535, and codingcomponent 1545. Any or all of these circuitry components may beimplemented with part or all of one or more ICs of processing system1510.

Transmitter circuitry 1505 operates to transmit or not transmittransmitter signals with one or more transmitter electrodes in any ofthe manners or their equivalents which have been described herein. Forexample, in a given time interval, transmitter circuitry 1505 may causeone or more transmitter electrodes of a plurality of transmitterelectrodes to transmit. Where there are multiple concurrenttransmissions, transmitter circuitry 1505 may be configured to causetransmissions that are not coded, or that are coded.

Receiver circuitry 1515 operates to receive, via receiver electrodes,resulting signals with responses that correspond to the transmittedtransmitter signals in any of the manners or their equivalents whichhave been described herein. For example, receiver electrodes may receivein series (one at a time) or in parallel (multiple receiver electrodesreceive concurrently).

Where transmitter circuitry 1505 is located in multiple ICs, a same ICmay operate and cause transmissions by transmitter electrodes in thesame or in different sections. Also, different ICs of transmittercircuitry 1505 may operate and cause transmissions by transmitterelectrodes in the same or in different sections.

Similarly, where receiver circuitry 1515 is located in multiple ICs, asame IC may operate and receive resulting signals from receiverelectrodes in the same or in different sections. Also, different ICs ofreceiver circuitry 1515 may receive resulting signals from receiverelectrodes in the same or in different sections.

The resulting signals include the responses corresponding to thetransmitter signals. A response corresponding to a transmitter signalreflects the effect of the transmitter signal on the receiver electrodethrough their capacitive coupling. These resulting signals also includeeffects due of interference (e.g., environmental noise), etc. Aresulting signal received by a receiver electrode may include responsesfrom multiple transmitter signals, such as when multiple transmitterelectrodes proximate to the receiver electrode transmit concurrently.

In one embodiment comprising multiple ICs that implement receivercircuitry 1515, the responses derived from the resulting signals arescaled or otherwise adjusted such that the responses provided by the ICsare comparable. For example, the values provided by the different ICsmay be compared to different baseline values corresponding to those ICs.As another example, a first IC may provide a first value proportional tothe first response corresponding to a first transmitter signal and asecond IC may provide a second value proportional to a second responsecorresponding to the first transmitter signal or a second transmittersignal. The first and second values may differ due to differencesbetween the first and second ICs (e.g., in gain), rather than becausethe actual electrical responses differ. The processing system 1510 mayuses calibration information stored in a memory, such as memory 1525, toadjust at least one of the first and second values such that they arecomparable.

The processing system 1510 may use the calibration information to adjustthe first value to produce a first adjusted value, such that a firstproportionality of the first adjusted value to the first response issubstantially equal to a second proportionality of the second value tothe second response. This adjusts one value to match another value. Asanother example, the processing system 1510 may use the calibrationinformation to adjust both the first and second values to produce firstand second adjusted values, respectively, such that a firstproportionality of the first adjusted value to the first response issubstantially equal to a second proportionality of the second adjustedvalue to the second response. This adjusts multiple values to a commonscale. Adjusting values facilitates normalizing responses acrossdifferent ICs, and can help compensate for differences between differentcircuitry (such as in amplification). These adjustments may be linear ornon-linear.

Calibration information for producing adjusted values may be obtained byperforming calibration functions with ICs. For example, duringmanufacture, output values to known input may be obtained at anappropriate level (e.g., per IC, per receiver electrode, per pixel) andused to produce this calibration information. This calibrationinformation may be stored in memory 1525. In some embodiments withmultiple ICs, each IC has a part of memory 1525 for storing calibrationinformation for the receiver electrodes and circuitry associated withthat IC; and, each SEIC adjusts the values that it provides. In someembodiments with multiple ICs including a central controller (such asthe central controller 1310 and 1410 of FIGS. 13-14), the centralcontroller stores the calibration values and calibrates the valuesreceived from the SEICs. In some embodiments with multiple ICs includingSEICs and a central controller, both the SEIC(s) and the centralcontroller store calibration information and adjust values. For example,each SEIC may store a correction function or table for calibratingbetween receiver circuits of that SEIC, and the central controller maystore a correction function or table for calibrating between SEICs.

The processing system 1510 may also comprise analysis circuitry 1535.This analysis circuitry is configured to receive information based on afirst response that is itself received by a first receiver circuit froma first receiver electrode. The analysis circuitry is also configured toreceive information based on a second response that is itself receivedby a second receiver circuit from a second receiver electrode. The firstand second receiver circuits are part of receiver circuitry 1515, andmay be part of a same IC or parts of different ICs. The analysiscircuitry 1535 may be configured to perform the adjustments describedabove

In some embodiments, the analysis circuitry 1535 is also configured toestimate amounts of capacitive coupling associated with differentpixels. In embodiments with a plurality of split pixels, the analysiscircuitry 1535 estimates amounts of capacitive coupling associated withthe split pixels using information based on responses of the appropriatepartial pixels. Analysis circuitry 1535 may make this estimate in anyappropriate way, including by combining partial pixel measurements. Insome instances, partial pixel measurements are scaled or adjusted asappropriate (e.g., using calibration information from memory 1525). Suchscaling or adjusting is more likely if separate ICs contain the receivercircuitry associated with the partial pixels of a split pixel.

As a specific example, analysis circuitry 1535 first receivesinformation from all of the partial pixels that make up a spit pixel.Then, analysis circuitry 1535 applies a weighting to at least onepartial pixel of the split pixel. This adjusts the contribution(s) ofthe partial pixels such that they are comparable. The weighting can bebased, among other bases, on a size, shape, or arrangement of the sensorelectrodes providing the localized capacitive coupling of the at leastone partial pixel. Then, analysis circuitry 1535 may sum theweighted/unweighted measurements of the partial pixels to produce anestimate of the capacitive coupling of the split pixel.

Analysis circuitry 1535 may also perform other functions. For example,analysis circuitry 1535 may compile a frame image from the differentpixel responses received from the multiple sections of a sectionedsensor pattern.

The processing system 1510 may also include coding component 1545. Whenincluded in processing system 1510, coding component 1545 operates touniquely encode transmitter signals that are concurrently transmittedwith at least two of the plurality of transmitter electrodes of a sensorpattern. Several examples of coding that may be accomplished by codingcomponent 1545 are described above. Such coding can assist indifferentiating received responses that are intermixed in a sameresulting signal due to concurrent transmission of transmitter signals.

Example Method of Capacitive Sensing

FIGS. 16A and 16B illustrate a flow diagram 1600 of an example method ofcapacitive sensing with a capacitive sensing device, according tovarious embodiments. The capacitive sensing device comprises a pluralityof transmitter electrodes sectioned by an ohmic seam and a plurality ofreceiver electrodes sectioned by the ohmic seam. For purposes ofillustration, reference will be made to sensor pattern 600 of FIG. 6;however, it is appreciated that procedures described in the method offlow diagram 1600 may be implemented using other sensor patterns,including other sensor patterns described herein and their equivalents.For example, the flow diagram 1600 also applies to sensor patterns withmore or fewer transmitter or receiver seams, with more or fewersections, with split pixels, and the like. Additionally, for purposes ofillustration, reference will be made to processing system 110 of FIG. 1and processing system 1510 of FIG. 15; however, it is appreciated thatin other implementations another component (e.g. a host compute) mayimplement some or all of the procedures illustrated in flow diagram1600. In some embodiments, not all of the procedures described in flowdiagram 1600 are implemented. In some embodiments, other procedures inaddition to those described may be implemented. In some embodiments,procedures described in flow diagram 1600 may be implemented in adifferent order than illustrated and/or described.

At 1610 of flow diagram 1600, in one embodiment, a first transmittersignal is transmitted with a first transmitter electrode of a pluralityof transmitter electrodes. The first transmitter electrode is disposedon a first side of an ohmic seam. With reference to FIG. 6, in onemethod of operating an embodiment with sensor pattern 600, thiscomprises transmitting a first transmitter signal with a sensorelectrode in one of sections 1-4 (e.g., TX1,1).

At 1620 of flow diagram 1600, in one embodiment, a second transmittersignal is transmitted with a second transmitter electrode of theplurality of transmitter electrodes. The second transmitter electrode isdisposed on a second side of an ohmic seam from the first transmitterelectrode. With reference again to FIG. 6, in one method of operating anembodiment with sensor pattern 600, this comprises transmitting with atransmitter electrode in another one of sections 1-4, which may beseparated by ohmic seam 605 or ohmic seam 615.

In one embodiment, the ohmic seam of 1610 and 1620 is a transmitterseam, and the second transmitter electrode is disposed opposite thefirst transmitter electrode (e.g., TX2,1 is opposite TX1,1 acrosstransmitter seam 605). In one such embodiment, transmitting the secondtransmitter signal with the second transmitter electrode may comprise:transmitting the second transmitter signal with the second transmitterelectrode during a second time period which overlaps at least partiallywith a first time period during which the first transmitter signal istransmitted with the first transmitter electrode. Such overlap may bepartial or complete, in various embodiments.

In one embodiment, the ohmic seam of 1610 and 1620 is a receiver seamand the second receiver electrode is disposed from first receiverelectrode in a non-adjacent manner (e.g., TX3,2 is disposed on adifferent side of receiver seam 615 than TX1,1 and is not adjacent toTX1,1). In one such embodiment, the transmitting of the secondtransmitter signal with the second transmitter electrode may comprise:transmitting the second transmitter signal with the second transmitterelectrode during a second time period which overlaps at least partiallywith a first time period during which the first transmitter signal istransmitted with the first transmitter electrode. Such overlap may bepartial or complete, in various embodiments.

In one embodiment, the ohmic seam of 1610 and 1620 is a receiver seam,and the second receiver electrode is disposed in an adjacent manner tothe first receiver electrode (e.g., TX3,1 is disposed on the a differentside of receiver seam 615 than TX1,1 and is also adjacent TX1,1). In onesuch embodiment, the transmitting the second transmitter signal with asecond transmitter electrode may comprise: transmitting the secondtransmitter signal with the second transmitter electrode during a secondtime period which non-overlaps at least partially with a first timeperiod during which the first transmitter signal is transmitted with thefirst transmitter electrode. Such non-overlap may be partial, or beoverlap at all.

At 1630 of flow diagram 1600, in one embodiment, a first responsecorresponding to the first transmitter signal is received with a firstreceiver electrode of the plurality of receiver electrodes, where thefirst receiver electrode is disposed on the first side of the ohmicseam. With continued reference to the example of FIG. 6, this cancomprise receiving with any receiver electrode in the same section asthe first transmitter electrode.

At 1640 of flow diagram 1600, in one embodiment, a second responsecorresponding to the second transmitter signal is received with a secondreceiver electrode of the plurality of receiver electrodes, where thesecond receiver electrode is on the second side of the ohmic seam. Withcontinued reference to the example of FIG. 6, this can comprisereceiving with any receiver electrode the same section as the secondtransmitter electrode.

At 1650 of flow diagram 1600, in one embodiment, the method furtherincludes: transmitting transmitter signals in a sequence spatiallymoving relative to the ohmic seam (which could be a receiver seam). Thesequence can be a first sequence that moves away from the ohmic seam ora second sequence that moves towards the ohmic seam. A variety of suchsequences have been described herein.

At 1660 of flow diagram 1600, a third transmitter electrode is disposedon the first side of the ohmic seam, and the method of flow diagram 1600further includes transmitting a third transmitter signal with the thirdtransmitter electrode concurrently with the transmitting of the firsttransmitter signal with the first transmitter electrode. Thistransmission is made such that the first receiver electrode receives aresulting signal that combines the first response and a third responsecorresponding to the third transmitter signal. The first transmittersignal and the third transmitter signal may be uniquely coded in any ofthe manners or their equivalents which have been described herein.

A 1670 of flow diagram 1600, independent results associated with thefirst response and the third response are determined using the resultingsignal. In some embodiments, analysis circuitry such as analysiscircuitry 1535 of processing system 1510 (see FIG. 15) can decode byutilizing the unique coding of the first and second transmitter signals,and thus determining independent results from the combined resultingsignal.

Thus, the embodiments and examples set forth herein were presented inorder to best explain the present invention and its particularapplication and to thereby enable those skilled in the art to make anduse the invention. However, those skilled in the art will recognize thatthe foregoing description and examples have been presented for thepurposes of illustration and example only. The description as set forthis not intended to be exhaustive or to limit the invention to theprecise form disclosed.

1. A transcapacitive sensing device having an ohmic seam, saidtranscapacitive sensing device comprising: a plurality of transmitterelectrodes, wherein said plurality of transmitter electrodes issectioned by said ohmic seam; a plurality of receiver electrodes,wherein said plurality of receiver electrodes is sectioned by said ohmicseam; and a processing system communicatively coupled with saidplurality of transmitter electrodes and said plurality of receiverelectrodes, said processing system configured to: transmit a firsttransmitter signal with a first transmitter electrode of said pluralityof transmitter electrodes, wherein said first transmitter electrode isdisposed on a first side of said ohmic seam; transmit a secondtransmitter signal with a second transmitter electrode of said pluralityof transmitter electrodes, wherein said second transmitter electrode isdisposed on a second side of said ohmic seam; receive a first responsecorresponding to said first transmitter signal with a first receiverelectrode of said plurality of receiver electrodes, wherein said firstreceiver electrode is disposed on said first side of said ohmic seam;and receive a second response corresponding to said second transmittersignal with a second receiver electrode of said plurality of receiverelectrodes, wherein said second receiver electrode is disposed on saidsecond side of said ohmic seam.
 2. The transcapacitive sensing device ofclaim 1, wherein said processing system comprises: a first receivercircuit configured to provide a first value proportional to said firstresponse; a second receiver circuit configured to provide a second valueproportional to said second response; and memory configured for storingcalibration information, said calibration information configured foradjusting said first value to produce a first adjusted value, wherein afirst proportionality of said first adjusted value to said firstresponse is substantially equal to a second proportionality of saidsecond value or an adjusted second value to said second response.
 3. Thetranscapacitive sensing device of claim 1, wherein said processingsystem comprises: a first receiver circuit disposed in a firstintegrated circuit, said first receiver circuit configured for receivingsaid first response from said first receiver electrode; a secondreceiver circuit disposed in a second integrated circuit, said secondreceiver circuit configured for receiving said second response from saidsecond receiver electrode, wherein said second integrated circuit isphysically separate from said first integrated circuit; and analysiscircuitry configured to receive information based on said first responsefrom said first receiver circuit and information based on said secondresponse from said second receiver circuit.
 4. The transcapacitivesensing device of claim 1, wherein said processing system comprises: acoding component configured for uniquely encoding transmitter signalsconcurrently transmitted with at least two of said plurality oftransmitter electrodes.
 5. The transcapacitive sensing device of claim1, wherein said processing system is further configured to: suspendtransmissions with said plurality of transmitter electrodes during anon-transmitting period.
 6. The transcapacitive sensing device of claim1, wherein said ohmic seam is a receiver seam, and wherein said secondreceiver electrode is disposed opposite said first receiver electrode,and wherein said first transmitter electrode is disposed adjacent tosaid second transmitter electrode.
 7. The transcapacitive sensing deviceof claim 1, wherein said ohmic seam is a transmitter seam, and whereinsaid second transmitter electrode is disposed opposite said firsttransmitter electrode, and wherein said second receiver electrode isdisposed adjacent to said first receiver electrode.
 8. Thetranscapacitive sensing device of claim 1, wherein said ohmic seam is atransmitter seam, wherein said second transmitter electrode is disposedopposite to said first transmitter electrode, and wherein saidprocessing system is configured to: concurrently transmit said firsttransmitter signal with said first transmitter electrode and said secondtransmitter signal with said second transmitter electrode.
 9. Thetranscapacitive sensing device of claim 1, wherein said ohmic seam is areceiver seam, wherein said second transmitter electrode is disposednon-adjacent to said first transmitter electrode, and wherein saidprocessing system is configured to: concurrently transmit said firsttransmitter signal with said first transmitter electrode and said secondtransmitter signal with said second transmitter electrode.
 10. Thetranscapacitive sensing device of claim 1, wherein said plurality oftransmitter electrodes is further sectioned by a second ohmic seam, andwherein said plurality of receiver electrodes is further sectioned bysaid second ohmic seam.
 11. The transcapacitive sensing device of claim10, wherein said ohmic seam is a first receiver seam, and wherein saidsecond ohmic seam is a second receiver seam.
 12. The transcapacitivesensing device of claim 10, wherein said ohmic seam is a transmitterseam, and wherein said second ohmic seam is a receiver seam.
 13. Amethod of capacitive sensing with a capacitive sensing device comprisinga plurality of transmitter electrodes sectioned by an ohmic seam and aplurality of receiver electrodes sectioned by said ohmic seam, saidmethod comprising: transmitting a first transmitter signal with a firsttransmitter electrode of said plurality of transmitter electrodes,wherein said first transmitter electrode is disposed on a first side ofsaid ohmic seam; transmitting a second transmitter signal with a secondtransmitter electrode of said plurality of transmitter electrodes,wherein said second transmitter electrode is disposed on a second sideof said ohmic seam; receiving a first response corresponding to saidfirst transmitter signal with a first receiver electrode of saidplurality of receiver electrodes, wherein said first receiver electrodeis disposed on said first side of said ohmic seam; and receiving asecond response corresponding to said second transmitter signal with asecond receiver electrode of said plurality of receiver electrodes,wherein said second receiver electrode is on said second side of saidohmic seam.
 14. The method as recited in claim 13, wherein said ohmicseam is a receiver seam, wherein a third transmitter electrode of saidplurality of transmitter electrodes is disposed on said first side andfarther from said receiver seam than said first transmitter electrode,and wherein a fourth transmitter electrode of said plurality oftransmitter electrodes is disposed on said second side and farther fromsaid receiver seam than said second transmitter electrode, said methodfurther comprising: transmitting transmitter signals in a sequencespatially moving relative to said receiver seam, wherein said sequenceis selected from the group consisting of: a first sequence moving awayfrom said receiver seam, and a second sequence moving towards saidreceiver seam; wherein said first sequence corresponds to: transmittinga third transmitter signal with said third transmitter electrode aftersaid transmitting said first transmitter signal with said firsttransmitter electrode; and transmitting a fourth transmitter signal withsaid fourth transmitter electrode after said transmitting said secondtransmitter signal with said second transmitter electrode; and whereinsaid second sequence corresponds to: transmitting a third transmittersignal with said third transmitter electrode before said transmittingsaid first transmitter signal with said first transmitter electrode; andtransmitting a fourth transmitter signal with said fourth transmitterelectrode before said transmitting said second transmitter signal withsaid second transmitter electrode.
 15. The method as recited in claim13, wherein said ohmic seam is a transmitter seam, wherein said secondtransmitter electrode is disposed opposite said first transmitterelectrode, and wherein said transmitting said second transmitter signalwith a second transmitter electrode comprises: transmitting said secondtransmitter signal with said second transmitter electrode during asecond time period which overlaps at least partially with a first timeperiod during which said first transmitter signal is transmitted withsaid first transmitter electrode.
 16. The method as recited in claim 13,wherein said ohmic seam is a receiver seam, wherein said second receiverelectrode is disposed opposite said first receiver electrode, whereinsaid second transmitter electrode is disposed non-adjacent to the firsttransmitter electrode, and wherein said transmitting said secondtransmitter signal with a second transmitter electrode comprises:transmitting said second transmitter signal with said second transmitterelectrode during a second time period which overlaps at least partiallywith a first time period during which said first transmitter signal istransmitted with said first transmitter electrode.
 17. The method asrecited in claim 13, wherein said ohmic seam is a receiver seam, whereinsaid second receiver electrode is disposed opposite said first receiverelectrode, wherein said second transmitter electrode is disposedadjacent to said first transmitter electrode, and wherein saidtransmitting said second transmitter signal with a second transmitterelectrode comprises: transmitting said second transmitter signal withsaid second transmitter electrode during a second time period whichnon-overlaps at least partially with a first time period during whichsaid first transmitter signal is transmitted with said first transmitterelectrode.
 18. The method as recited in claim 13, wherein a thirdtransmitter electrode is disposed on said first side of said ohmic seam,said method further comprising: transmitting a third transmitter signalwith said third transmitter electrode concurrently with saidtransmitting a first transmitter signal with said first transmitterelectrode, such that said first receiver electrode receives a resultingsignal that combines said first response and a third responsecorresponding to said third transmitter signal; and determiningindependent results associated with said first response and said thirdresponse using said resulting signal.
 19. A transcapacitive sensorelectrode arrangement comprising: a plurality of transmitter electrodesaligned along a first direction and sectioned by an ohmic seam; and aplurality of receiver electrodes aligned along a second directionnon-parallel to said first direction and sectioned by said ohmic seam,wherein said plurality of transmitter electrodes and said plurality ofreceiver electrodes form a plurality of split pixels coinciding withsaid ohmic seam.
 20. The transcapacitive sensor electrode arrangement ofclaim 19, wherein said ohmic seam is a receiver seam overlapping a firsttransmitter electrode of said plurality of transmitter electrodes, andwherein each of said plurality of split pixels is formed from said firsttransmitter electrode and at least two receiver electrodes of saidplurality of receiver electrodes.
 21. The transcapacitive sensorelectrode arrangement of claim 19, wherein said ohmic seam is atransmitter seam overlapping a first receiver electrode of saidplurality of receiver electrodes, and wherein each of said plurality ofsplit pixels is formed from said first receiver electrode and at leasttwo transmitter electrodes of said plurality of transmitter electrodes.22. A processing system configured for operating a capacitive sensingdevice, the processing system comprising: transmitter circuitryconfigured to transmit with a plurality of transmitter electrodes ofsaid capacitive sensing device, said plurality of transmitter electrodesdisposed along a first axis and sectioned by an ohmic seam; receivercircuitry configured to receive with a plurality of receiver electrodesof said capacitive sensing device, said plurality of receiver electrodesdisposed along a second axis non-parallel to said first axis andsectioned by said ohmic seam, wherein said plurality of transmitterelectrodes and said plurality of receiver electrodes form a plurality ofsplit pixels coinciding with said ohmic seam; and analysis circuitryconfigured to estimate an amount of capacitive coupling associated witheach split pixel of said plurality of split pixels.
 23. The processingsystem of claim 22, wherein said analysis circuitry is configured toestimate an amount of capacitive coupling associated with each splitpixel of said plurality of split pixels by: for each split pixel of saidplurality of split pixels, combining associated partial pixelmeasurements obtained using said plurality of receiver electrodes. 24.The processing system of claim 22, wherein said analysis circuitry isconfigured to estimate an amount of capacitive coupling associated witheach split pixel of said plurality of split pixels by: applying aweighting for at least one partial pixel of said plurality of splitpixels based on an amount of signal amplification associated with saidat least one partial pixel.